Smooth bromegrass seeds were submerged in water for four days, following which they were planted in six pots, each measuring 10 cm in diameter and 15 cm in height. These pots were positioned in a greenhouse and maintained under a 16-hour photoperiod, with a temperature range of 20-25°C and a relative humidity of 60%. The strain's microconidia, developed on wheat bran for ten days, were subsequently washed with sterile deionized water, filtered through three sterile cheesecloth layers, quantified, and diluted to one million microconidia per milliliter using a hemocytometer. At a height of approximately 20 centimeters, three pots of plants were sprayed with a spore suspension, 10 milliliters per pot, while the remaining three pots served as control groups, being treated with sterile water (LeBoldus and Jared 2010). Under controlled conditions provided by an artificial climate box, inoculated plants were cultured, experiencing a 16-hour photoperiod with a temperature of 24 degrees Celsius and a relative humidity of 60 percent. Brown spots developed on the leaves of the treated plants following a five-day period, in stark contrast to the healthy condition of the control group's leaves. Re-isolation of the same E. nigum strain from inoculated plants was confirmed using the previously described morphological and molecular identification techniques. To our understanding, this represents the initial documentation of leaf spot disease, attributable to E. nigrum, on smooth bromegrass within China, and globally. Smooth bromegrass's agricultural output and quality might be affected by infection with this pathogen. Therefore, the development and execution of strategies for managing and controlling this condition are essential.
*Podosphaera leucotricha*, the fungus responsible for apple powdery mildew, is an endemic pathogen globally where apples are produced. In the absence of robust host defenses, conventional orchards typically rely on single-site fungicides for the most effective disease management. Erratic precipitation and rising temperatures in New York State, a consequence of climate change, are likely to foster a more favorable environment for apple powdery mildew to flourish and propagate. Apple powdery mildew's prevalence in this situation could potentially displace the established management strategies for apple scab and fire blight. Producer feedback regarding fungicide efficacy on apple powdery mildew remains absent, yet the authors have witnessed and recorded an escalation in cases of this disease. To confirm the effectiveness of key fungicide categories—FRAC 3 (demethylation inhibitors, DMI), FRAC 11 (quinone outside inhibitors, QoI), and FRAC 7 (succinate dehydrogenase inhibitors, SDHI)—a determination of P. leucotricha populations' fungicide resistance was required. From 43 orchards across New York's leading agricultural regions, we collected 160 samples of P. leucotricha over two years (2021-2022). These orchards represented conventional, organic, low-input, and unmanaged agricultural practices. find more To identify mutations in the target genes (CYP51, cytb, and sdhB), samples were screened, historically known to confer fungicide resistance in other fungal pathogens to the DMI, QoI, and SDHI fungicide classes, respectively. Indian traditional medicine The analysis of all samples demonstrated no nucleotide sequence mutations within the target genes that resulted in problematic amino acid substitutions. Consequently, New York P. leucotricha populations remain susceptible to DMI, QoI, and SDHI fungicides, contingent upon no other resistance mechanisms being operational.
American ginseng's yield is directly correlated with the use of seeds. For both the long-distance spread of pathogens and their survival, seeds are absolutely essential. To effectively manage seed-borne diseases, the pathogens carried by the seeds must be understood. High-throughput sequencing, combined with incubation techniques, was employed to identify and characterize the fungal organisms harbored by American ginseng seeds procured from key Chinese production areas in this research. New Rural Cooperative Medical Scheme Seed-borne fungi were observed at a rate of 100%, 938%, 752%, and 457% in Liuba, Fusong, Rongcheng, and Wendeng, respectively. Seeds yielded sixty-seven fungal species, representing twenty-eight genera. Upon examination, eleven pathogens were detected within the seed samples. Every seed sample contained a presence of Fusarium spp. pathogens. A higher relative abundance of Fusarium species was found in the kernel compared to the shell. A significant difference in fungal diversity was observed between seed shells and kernels, as revealed by the alpha index. A non-metric multidimensional scaling procedure isolated samples from different provinces and those originating from either seed shells or kernels, indicating a clear separation. Seed-carried fungi in American ginseng responded differently to various fungicides. Tebuconazole SC demonstrated the highest inhibition rate (7183%), while Azoxystrobin SC (4667%), Fludioxonil WP (4608%), and Phenamacril SC (1111%) showed lower rates. Seed-borne fungi associated with American ginseng were shown to be only slightly inhibited by fludioxonil, a traditional seed treatment agent.
Global agricultural trade's rapid growth has been closely associated with the arrival and reappearance of novel plant diseases. The fungal pathogen Colletotrichum liriopes, a foreign quarantine concern for ornamental plants, particularly Liriope spp., continues to be a problem in the United States. Although this species has been documented in various asparagaceous hosts across East Asia, its inaugural and sole sighting within the United States occurred in 2018. That investigation, however, relied only on the ITS nrDNA region for species determination and no corresponding cultured or vouchered specimen was stored. The present study's central objective was to identify the geographic and host range of samples classified as C. liriopes. The ex-type of C. liriopes was employed as a reference standard for the comparative evaluation of isolates, sequences, and genomes from various hosts and geographic locations, including, but not limited to, China, Colombia, Mexico, and the United States, to facilitate this objective. Multilocus phylogenetic analyses (including ITS, Tub2, GAPDH, CHS-1, and HIS3), phylogenomic studies, and splits tree analyses underscored the formation of a robust clade by all the examined isolates/sequences, displaying a negligible degree of intraspecific variance. Detailed morphological characteristics align with the observed findings. Recent introduction and spread of East Asian genotypes to countries where ornamental plants are produced, exemplified by the low nucleotide diversity, negative Tajima's D in multilocus and genomic datasets, and the Minimum Spanning Network, is suspected to have happened initially to South America, and subsequently into importing countries like the USA. The study reports a significant expansion in the geographic and host range of C. liriopes sensu stricto, encompassing the USA (including states such as Maryland, Mississippi, and Tennessee) and including various host species besides those traditionally found in Asparagaceae and Orchidaceae. The present research produces fundamental knowledge, applicable to the reduction of trade losses and expenses in agriculture, and to furthering our understanding of pathogen dispersal patterns.
Edible fungus Agaricus bisporus is a widely cultivated and popular choice across the world. During December 2021, a 2% incidence of brown blotch disease was observed on the cap of A. bisporus cultivated in a mushroom base in Guangxi, China. At the outset, brown blotches (ranging from 1 to 13 centimeters) manifested on the cap of the A. bisporus, gradually enlarging as the cap developed in size. The infection's progression, over two days, involved the penetration of inner tissues within the fruiting bodies, characterized by the appearance of dark brown blotches. For causative agent isolation, 555 mm internal tissue samples from infected stipes were treated with 75% ethanol for 30 seconds, and then thoroughly rinsed three times with sterile deionized water (SDW). Following this, the samples were homogenized within sterile 2 mL Eppendorf tubes, to which 1000 µL SDW was added. This suspension was serially diluted into seven concentrations (10⁻¹ to 10⁻⁷). Suspensions (120 liters each) were spread across Luria Bertani (LB) medium, followed by a 24-hour incubation at 28 degrees Celsius. Whitsh-grayish in color, the dominant single colonies were smooth and convex in shape. On King's B medium (Solarbio), Gram-positive cells were non-flagellated, nonmotile, and lacked the formation of pods, endospores, and fluorescent pigments. Amplification of the 16S rRNA gene (1351 base pairs; OP740790) from five colonies, using the universal primers 27f/1492r (Liu et al., 2022), resulted in a 99.26% similarity to Arthrobacter (Ar.) woluwensis. Employing the Liu et al. (2018) methodology, amplified partial sequences of the ATP synthase subunit beta (atpD) gene (677 bp; OQ262957), RNA polymerase subunit beta (rpoB) gene (848 bp; OQ262958), preprotein translocase subunit SecY (secY) gene (859 bp; OQ262959), and elongation factor Tu (tuf) gene (831 bp; OQ262960) from colonies exhibited remarkable similarity (over 99%) to Ar. woluwensis. Three isolates (n=3), analyzed with bacterial micro-biochemical reaction tubes (Hangzhou Microbial Reagent Co., LTD), demonstrated biochemical properties equivalent to those of Ar. Woluwensis is positive for esculin hydrolysis, urea metabolism, gelatinase activity, catalase production, sorbitol utilization, gluconate metabolism, salicin fermentation, and arginine utilization. No citrate, nitrate reduction, or rhamnose utilization was observed (Funke et al., 1996). Analysis of the isolates indicated they are Ar. The woluwensis classification, established through meticulous morphological analysis, biochemical testing, and phylogenetic investigation, provides a robust framework for understanding its characteristics. Pathogenicity assessments were conducted on bacterial suspensions, grown in LB Broth at 28°C with 160 rpm agitation for 36 hours, at a concentration of 1 x 10^9 CFU/ml. A 30-liter quantity of bacterial suspension was applied to the caps and tissues of immature A. bisporus fungi.